Cloud computing is changing the way that enterprises and consumers utilize applications and carry on their tasks. In cloud computing, data and applications are stored over the Internet instead of local storage, and instead of owning all the hardware and software where data and applications reside, an enterprise or a consumer (the “client” or “tenant”) utilizes some or majority of the needed hardware and software owned by a cloud provider, which may utilize data centers (sometimes referred to as “datacenters”) to store the data and run the applications. Data set migration is a common operation in a cloud computing environment, where the migration of a data set typically refers to relocating the state of a virtual machine, including its memory and storage. Data set migration may happen within a data center, and it may also happen between data centers, which are often geographically separated.
When data set migration occurs between data centers that are geographically separated, a communication network is typically deployed to connect the data centers. The communication network may include a wavelength switched optical network. A wavelength switched optical network offers a high line speed (e.g., 10G-40G bits/second) for data set migration, thus potentially may complete data set migration very quickly. Yet a wavelength switched optical network is a circuit switching network, which requires setting up prior to being utilized to transfer data. Unlike a packet switching network, where no setup time or minimum setup time (e.g., milliseconds) is required, a wavelength switched optical network generally takes much longer time (seconds, minutes, or even longer) to set up a wavelength path. Thus, the configuration of a wavelength switched optical network is relatively static.
In contrast, data set migration in a cloud computing environment can be on demand. End user behaviors, network conditions, server loads in the data centers, power saving policies and other factors may cause the need of data set migration changes dynamically, and it is a challenge to set up a circuit switched network such as a switched optical network efficiently to accommodate the dynamic needs of data set migration.